The present invention, in some embodiments thereof, relates to an odorant mixture and, more particularly, but not exclusively, to an odorant mixture having an olfactory signature, and method of characterizing an odorant mixture using its olfactory signature.
Several studies have linked human perception of monomolecular odorants to the odorant's physical structure and its specific receptors [Khan et al. (2007) Predicting odor pleasantness from odorant structure: pleasantness as a reflection of the physical world, The Journal of Neuroscience 27(37):10015; Kermen et al. (2011) Molecular complexity determines the number of olfactory notes and the pleasantness of smells, Sci Rep 1:206; Keller et al., (2007) Genetic variation in a human odorant receptor alters odour perception, Nature 449(7161):468-472; and Menashe et al. (2007) Genetic elucidation of human hyperosmia to isovaleric acid. PLoS Biol 5(11):e284].
Odors are complex mixtures of chemical species, and so contain many constituent molecules. The biological olfactory system is a remarkable sensor having many olfactory cells or odorant receptors, but not very many different types of olfactory cells. The characterization of a scent or odor is typically through the combined response of many of the receptors.
Haddad et al. [A metric for odorant comparison, Nature Methods—5, 425-429 (2008)] describes a multidimensional physicochemical metric that took into account many molecular descriptors. Molecular descriptors are mathematical values that describe the structure or shape of a molecule. In Haddad et al., each odorant molecule is represented as a vector containing its descriptor values, and the Euclidean distance between any two odorants is used as a multidimensional metric.
Additional background art includes Saito et al., “Odor Coding by a Mammalian Receptor Repertoire”, Sci. Signal. 2, ra9 (2009).